The Simple Fix for Proper Plank Form to Work Your Core Even Harder

Ah, the mighty plank. When you've mastered proper plank form, this move can set your abs on fire and transform your workouts. It's an incredibly useful exercise to know and to love (or hate, depending on the day). "Planks are a crucial component of exercise routines because they are engaging practically your entire body in a safe position," Amanda Christodoulou, certified Pilates instructor and owner of Pilates Body in Miami, tells SELF. Safe, effective, tough, and total-body engaging—doesn't get much better than that.

There's just one catch: Proper plank form is tough.

For planks to live up to their full potential, you've got to make sure your form is on point—and that can be a lot easier said than done. "A proper plank, when turned vertically, is close to proper standing posture," Christodoulou says, which means doing a proper plank is hard. And you might not even realize that you're not doing them right.

This can lead to your body finding sneaky ways to make this move a little bit easier, sometimes without you even realizing it. "When faced with challenging positions, our bodies tend to overcompensate with the strongest and/or largest muscles, making it easy to slip into improper form," says Christodoulou.

One of the biggest plank mistakes is performing the exercise with "an exaggerated dip in the lower back," Christodoulou says. "If your lower back is sagging, your core is likely not engaged." This error in form also shortens your lower back, which can cause tightness and worsen your posture.

The good news: There's an easy way to fix a droopy lower back.

This plank-perfecting tweak is incredibly easy to understand, unlike some admittedly nebulous fitness terminology (and a little harder to execute, only because it's ensuring you're actually doing the plank right). I found out about this tweak during a class at Fuse Pilates, when founder Mariska Breland told us to stick our butts up while we held (and held, and held...) a plank, then tuck our butts under.

Voilà, a plank with a nice, straight back, instead of one that sags like a years-old mattress. After I followed Breland's instructions, the plank was immediately harder, which I saw as a good sign that my core was more engaged than before. As Christodoulou notes, "You will instantly feel this tiny tweak in all the right places." You'll likely feel it later, too—the day after this class, laughing hurt much more than it usually does post-Pilates.

Ready to achieve that perfect plank?

Proper plank form means keeping your core and quads tight, and your hips lifted. For stability's sake, your feet (or knees) and arms (or elbows) should be shoulder-width apart. To keep your spine in a neutral position and avoid straining your neck, aim your chin about six inches in front of your body. And Christodoulou's email signature is "live.love.length." for good reason. As you hold the plank, imagine that you’re extending from the crown of your head through your heels. Lastly, don't hold your breath!

It's key to remain engaged throughout the entire plank, so don't let yourself zone out. Instead, incorporate Breland's special tweak to make sure the exercise is as effective as possible. Here's a look at the visible difference between good and bad plank form.